Lana Wood is her sister, not her daughter. She would know.
OK, her sister, not her daughter. But if she has proof that a forcible rape was committed on her sister, why wait until the perpetrator is dead? At that point both her sister and perp would be dead and neither can confirm nor refute her claim. And she would have to have some pretty good, irrefutable and actionable evidence to make such a claim, and if she has that, there is no reason to wait until the perp (presumably Kirk Douglass) is dead in order to do so.